Global Health Asia-Pacific July 2022 - Page 48

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A real-time blood test that can detect cancer

Blood analysis is already providing key information to treat several malignancies , but its potential as a screening tool is still uncertain
Beyond helping identify those who could benefit from early treatment , repeated blood testing could also inform us if the disease has been cured , which could help women to avoid agonising over whether their malignancy is going to come back .

Afundamental goal in cancer research is to be able to detect the disease early when it ’ s easier to treat and hasn ’ t spread to multiple tissues . It ’ s this lack of early detection that characterises many cancers and is ultimately responsible for many cancer deaths .

But there may be hope on the horizon . One of the most promising new technologies for identifying cancer is called liquid biopsy , a fancy term for detecting and monitoring cancer with blood-based tests .
“ I am really interested in the power of liquid biopsy for smarter and more personalised cancer treatment ,” said Dr Jacqui Shaw , Professor of Translational Cancer Genetics at the University of Leicester , who has been researching liquid biopsy for two decades in the hopes of improving early cancer detection .
Cancer cells as well as DNA fragments can escape the tumour in the bloodstream , and these circulating tumour cells and circulating tumour ( ct ) DNA can both be picked up by different blood tests to determine
Several blood-based tests have received the green light by health authorities the best treatment options or monitor how patients have responded to therapies . The hope is that this approach could one day offer a reliable method to improve cancer screening and detect early-stage cancers .
�n one of the most significant achievements of her work on breast cancer , Professor Shaw and her team conducted a clinical study that showed that ct DNAbased blood tests can help identify women at risk of relapse up to three years earlier than conventional methods like scans .
These findings have supported work by the diagnostics company Natera to develop a liquid biopsy test called Signatera , which was designed as a breakthrough device by the US Food and Drug Administration ( FDA ), a move aimed to speed up approval of medical devices that provide more effective treatment or diagnosis of life�threatening or irreversibly debilitating conditions .
This type of tests may lead to “ more personalised and earlier treatment ” post-operation , for example for patients with triple negative breast cancer , a subtype that is challenging to treat because it can progress rapidly after successful surgery , explained Professor Shaw . Many patients with breast cancer who undergo surgery to remove their tumour are subsequently treated with chemotherapy , radiotherapy , hormone or targeted therapies for varying periods of time depending on the type of breast cancer . The tricky part is to understand who ’ s going to benefit from post� op treatment and how long to treat patients to avoid relapse or overtreatment .
�eyond helping identify those who could benefit from early treatment , repeated blood testing could also inform us if the disease has been cured , which could help women to avoid agonising over whether their malignancy is going to come back . “ Breast cancer has a long period of up to 25 years after surgery during which the cancer can recur , so a regular negative blood test could provide women with an incredibly useful reassurance ,” she said .
This monitoring is also beneficial for patients with other malignancies as it can predict relapses in lung , colon , and bladder cancers .
Several other blood-based tests have already
46 JULY 2022 GlobalHealthAsiaPacific . com